Crypt Class: True Data Encryption and Decryption Class

Crypt Class README

Description:

Crypt Class is a wrapper around libmcrypt_ functions, it greatly simplifies the interface and adds
new features and simplies many things.  It provides an easy way to encrypt and decrypt data, it automatically
creates the IV and extracts it for you later.

Crypt Class stores the IV with the encrypted string so every time you encrypt a string it will look different
but decrypt to the original value.

Crypt Class also makes it easy to switch between encryption modes and ciphers.

Example:

Here is an example on how to encrypt the string "this is a test message" with the encryption key "test key".

<?php
   // include crypt class file
   include('crypt_class.php');
   
   // create an instance of the crypt class
   $crypt_class = new CRYPT_CLASS;
   
   // set the encryption cipher to twofish
   $crypt_class->set_cipher('twofish'); // set the cipher
   
   // set the mode to cfb (you should use cfb for strings and cbc for files)
   $crypt_class->set_mode('cfb'); // set encryption mode
   
   // set the encryption key to 'test key'
   $crypt_class->set_key('test key')
      
   // this is the data we want to encrypt
   $data = 'this is a test message';     
   
   // this will be the encrypted data  
   $encrypted = $crypt_class->encrypt($data);
   
   
   // this is the decrypted data
   $decrypted = $crypt_class->decrypt($encrypted);
?>



Author:

   Jason Sheets <jsheets@shadotech.com>
   10/5/02
   
Support

   Feel free to e-mail me if you need help but please look at http://www.php.net/mcrypt.
   

License:

This class is distributed under the BSD License.
   
Copyright (C) 2002 Jason Sheets <jsheets@shadonet.com>.
All rights reserved.

THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
   
2. Redistributions in binary form must reproduce the above copyright
   notice, this list of conditions and the following disclaimer in the
   documentation and/or other materials provided with the distribution.
   
3. Neither the name of the project nor the names of its contributors
   may be used to endorse or promote products derived from this software
   without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND
ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
ARE DISCLAIMED.  IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE
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